Problem: $\left[\begin{array} {ccc} 0& -5\\ -6& 2\\ -8& 5\\ -1& -9\\ -1& 0 \end{array}\right]$ What are the dimensions of the matrix?
Solution: The first dimension is the number of rows in the matrix. There are $5$ rows. The second dimension is the number of columns in the matrix. There are $2$ columns. In conclusion, the dimensions of the matrix are $5\times 2$.